TDA6502 Datasheet, PDF (21/44 Pages) NXP Semiconductors – 5 V mixers/oscillators and synthesizers for cable TV and VCR 2-band tuners

Philips Semiconductors
5 V mixers/oscillators and synthesizers for
cable TV and VCR 2-band tuners
Preliminary specification
TDA6502; TDA6502A;
TDA6503; TDA6503A
4. The frequency shift is defined as a change in oscillator frequency when the supply voltage varies from
V_CC = 5 to 4.75 V (4.5 V) or from V_CC = 5 to 5.25 V (5.5 V). The oscillator is free running during this measurement.
5. The frequency drift is defined as a change in oscillator frequency when the ambient temperature varies from
T_amb = 25 to 50 °C or from T_amb = 25 to 0 °C. The oscillator is free running during this measurement.
6. Switch-on drift is defined as the change in oscillator frequency between 5 s and 15 min after switch-on. The oscillator
is free running during this measurement.
7. The ripple susceptibility is measured for a 500 kHz ripple at the IF output using the measurement circuit of Fig.19;
the level of the ripple signal is increased until a difference of 53.5 dB occurs between the IF carrier fixed at 100 dBµV
and the sideband components.
8. This is the level of divider interferences close to the IF frequency. For example channel C: f_OSC = 179 MHz,
1_{⁄4 fOSC = 44.75 MHz. The VHFIN input must be left open (i.e. not connected to any load or cable); The UHFIN1 and}
UHFIN2 inputs are connected to a hybrid.
9. Crystal oscillator interference means the 4 MHz sidebands caused by the crystal oscillator. The rejection has to be
greater than 60 dB for an IF output signal of 100 dBµV.
10. The reference frequency rejection is the level of reference frequency sidebands related to the sound sub-carrier.
11. Channel 6 beat is the interfering product of f_RF(pix) + f_RF(snd) − f_OSC of channel 6 at 42 MHz.
12. Channel A-5 beat is the interfering product of f_RF(pix), f_IF and f_OSC of channel A-5: f_beat = 45.5 MHz.
The possible mechanisms are: f_OSC − 2 × f_IF or 2 × f_RF(pix) − f_OSC. For the measurement: V_RF = 80 dBµV.
handbook, full pagewidth
1
2
0.5
5
0.2
10
−j
∞
10 5
2
1
0.5
0.2 40 MHz
0
+j
10
400 MHz
5
0.2
2
0.5
1
FCE528
Fig.7 Input admittance (S₁₁) of the VHF mixer input (40 to 400 MHz); Y₀ = 20 mS.
2000 Mar 16
21